• The Korean Journal of Malacology
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• v.28 no.4
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• pp.329-333
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• 2012

The Korean muricid snails are listed include previous record and three unrecorded species, Morula iostoma, Coralliophila morishimai, and C. abnormis collected from Mudo of Jeju-do were redescribed. As a result, the family Muricidae in Korea turned out to be 44 species of 22 genera.

• Proceedings of the Zoological Society Korea Conference
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• 1999.10b
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• pp.172.1-172
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• 1999

No Abstract, See Full Text

• Animal cells and systems
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• v.3 no.3
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• pp.285-293
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• 1999

Allele frequencies in twenty-two populations from nine Korean muricid species of five genera (Rapaninae and Ocenebrinae) wire analyzed genetically using 13 loci from 11 allozyme systems. The clustering patterns of these species were basically consistent with traditional groupings to two subfamilial categories based on shell and radula morphologies. Within six ocenebrine species it was apparent that Ceratostoma inornata and Pteropurpura adunca were most closely related to each other than to any other species belonging to the genus Ceratostoma. These results, along with other anatomical features 〔morphologies of albumin gland (female), egg capsule〕, suggest that the generic position of C. inornata, previously classified to be congeneric with other western Pacific Ceratostoma species, should be reconsidered. Our results show the close relationship of Nucella freycineti with other ocenebrine species, rather than with rapanines, which supports a previous suggestion that the genus Nucella should be placed with the subfamily Ocenebrinae rather than the subfamily Rapaninae.

• Journal of Species Research
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• v.5 no.3
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• pp.530-532
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• 2016

A single specimen in the subfamily Coralliophilinae in Family Muricidae was collected from Jeju-do by SCUBA diving survey. It was identified as Hirtomurex nakamurai Kosuge, 1985 based on external morphological characteristics. The Coralliophilinae species, commonly known as coral snails, are broadly distributed in tropical and temperate oceans from shallow subtidal zones up to 1,000 m in depth. To date, only four Coralliophila species in the subfamily Coralliophilinae have been reported from Korean waters. Prior to this report, Hirtomurex species has not been reported from Korean waters yet. As a result of this study, a total of five species in two genera of subfamily Coralliophilinae are recorded as Korean mollusk fauna.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.36 no.6
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• pp.632-640
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• 2003

Geographic variation in shell morphology of Thais clavigera $(K\"{u}ster)$ (Gastropoda: Muricidae) was investigated using samples collected from 24 sites along the Korean coast. Multivariate statistical analysis was applied to 9 morphometric and 4 categorical variables. The shells of T. clavigera were classified into two distinct morph types (Type-W and -E). Temperature and salinity of the sampling sites were significantly correlated with the incidence of morph types. Relative abundance of Type-W (thin, yellowish brown shell with triangular nodules) was positively correlated with temperature and negatively correlated with salinity. In contrast, relative abundance of Type-E (thick, dark purple shell with round nodules) was negatively correlated with temperature and positively correlated with salinity. Possible correlation between environmental factors (temperature and salinity) and morphological variations in the shells were discussed.

• Animal Systematics, Evolution and Diversity
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• v.27 no.1
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• pp.1-17
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• 2011

Thais Roding, 1798, commonly known as rock-shell, is among the most frequently found gastropod genera worldwide on intertidal rocky shores including those of Japan, China, Taiwan and Korea. This group contains important species in many marine environmental studies but species-level taxonomy of the group is quite complicated due to the morphological variations in shell characters. This study examined the genetic variations and relationships among three Korean Thais species based on the partial nucleotide sequences of mitochondrial cox1 gene fragments. Phylogenetic trees from different analytic methods (maximum parsimony, neighbor-joining, and maximum likelihood) showed that T. bronni and T. luteostoma are closely related, indicating the most recent common ancestry. The low sequence divergence found between T. luteostoma and T. bronni, ranging from 1.53% to 3.19%, also corroborates this idea. Further molecular survey using different molecular marker is required to fully understand a detailed picture of the origin for their low level of interspecific sequence divergence. Sequence comparisons among conspecific individuals revealed extensive sequence variations within the three species with maximum values of 2.43% in T. clavigera and 1.37% in both T. bronni and T. luteostoma. In addition, there is an unexpectedly high level of mitochondrial genotypic diversity within each of the three Korean Thais species. The high genetic diversity revealed in Korean Thais species is likely to reflect genetic diversity introduced from potential source populations with diverse geographic origins, such as Taiwan, Hong Kong, and a variety of different coastal regions in South China and Japan. Additional sequence analysis with comprehensive taxon sampling from unstudied potential source populations will be also needed to address the origin and key factors for the high level of genetic diversity discovered within the three Korean Thais species studied.

• The Korean Journal of Malacology
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• v.9 no.2
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• pp.1-15
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• 1993

The reproductive ecology of the purple shell, Rapana venosa was investigated by the histological observations on depositions of the egg capsules, and hatching of larvae in the laboratory and the subtidal zone of the vicinity of piung-do, Chollabud-do, west coast of korea, for one year from June 1992 to May 1993. The results are summarized as follows:1. Rapana venosa is dioecious in sex. The ovary is composed of a number of ovarian lobules, and the testis comprises a number of ovarian lobules, and the testis comprises of gonads could be classified into 4 stages in males and 5 stages in females: 1) growing stage(in female subdivided into 2 stages of early and late growing stage). 2)mature stage. 3)spent stage or copulationstage. 4)rdcovering stage. The early growing stage in females of the purple shell was in September through February, late gorwing stage was in October to March, mature stage was in September to January, mature stage was in September to July, copulation stage was in Februaty to June and recovering stage in April to October.3. Spawning occurred 3-4 times at intervals of 1-3 days, and completed within 10 days from the beginning of spawning during the spawning season of the year.4. From the results of laboratory and field observations, egg masses are composed of a number of egg capsules, egg masses are occurred from May to late August, and in mid August depositions of egg mass in composed of 90-113 egg capsules, fecundity in an egg capsule was ranged 984 to 1,241 eggs(average 1,096 egg). Therefore, fecundity in total egg capsules spawned per individual during the spawning season is estimated as approximately 320,000 to 450,000 egges.5. The incubation period during deposition of an egg capsule to hatching larvad tood 17 days at 18.3-20.4%C(water temperature)and 1.021 (specific gravity fo sea water).

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2000.05a
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• pp.375-376
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• 2000

Sex ratio of a population is a key factor to determine reproductive rate of the population. If the population has skewed sex ratio to the male, the population size may decline gradually at an area which it inhabits, and, furthermore, if a species plays an ecologically important role in its community (e.g., a keystone species in Paine, 1966), its potential reproductive rate will be to form a characterized community because community structure is strongly influenced by the abundance of the ecologically important species (Hughes, 1986). A number of workers (e.g., Bryan et al., 1986 in Nucella lapillus; Spence et al., 1990 in Thais haemastoma) suggested that high frequency and/or late stage of imposex might affect the female mortality and normal reproduction adversely. Consequently, the imposex could affect sex ratio of natural population of some neogastropod including thaisid species. (omitted)

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2000.05a
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• pp.533-534
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• 2000

In general, intertidal gastropods display a considerable amount of intraspecific shell variation (De Wolf et al., 1998). Particularly, thaisid species, including Thais clavigera(=T.c.), have been shown a variety of shell variation in the world ocean (e.g. T, emerginata in Kitching, 1976). Nomura (1926) noted local variation of shell morphology based on five Japanese populations. Ahe (1985) classified Japanese T.c. into two forms (Form-C ＆. -P). In the Korean waters, a strong variation in nodule shape of T.c, shell has also been noted by Choe ＆ Park (1997). Taxonomy of T.c. is controversial so far. (omitted)

• Journal of Fisheries and Marine Sciences Education
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• v.27 no.4
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• pp.1031-1040
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• 2015

Ultrstructural studies of germ cell differentiation and vitellogenesis in the oocytes of the female Rapana venosa in the brackish water area of Seomjin River were investigated by transmission electron microscope observations. In the early vitellogenic oocytes, the Golgi complex and mitochondria were involved in the formation of glycogen particle, lipid droplets, and yolk granules. In the late vitellogenic oocytes, the rough endoplasmic reticulum and multivesicular bodies were involved in the formation of proteid yolk granules in the cytoplasm. However, heterosynthetic vitellogenesis in this species were not observed in vitellogenic oocytes during oogenesis. A mature yolk granule was composed of three components: crystalline core, electron lucent cortex and the limiting membrane. As shown in some large gastropods, vitellogenesis in R. venosa occurred by way of endogenous autosynthesis without heterosythetic vitellogenesis (exogeneous endocytosis), which are found in the oocytes in bivalves. The mating period and spawning activity were related with the increases of seawater temperatures and salinities.